Battery wiring C**** Up! Advise please

Mongoose · 04 June 2019, 19:28

ok,
fitted the battery back in the rib yesterday.
I have a positive and negative cable going from battery to a battery isolator.
The wiring loom in a corrugated 35mm pipe also runs along by the battery box going from centre consul and back to engine.
From this loom is a black cable about 4mm in diameter that also connects directly to the battery.
I just don't know if it came off positive or negative!
I did connect it to the negative battery terminal thinking it would be less of a issue if it was wrong,and everything seems to work-gauges/engine starting/ VHF/Plotter etc, but im 80% sure it was originally on the positive!
Should I just leave alone, or should I try it on the positive?
I don't really want to start frying fuses etc!

GuyC · 04 June 2019, 20:56

I'd just leave it alone although you could just disconnect it and see whether everything still works.

Poly · 04 June 2019, 22:18

where does the other end of the cable go?

gpsguru · 04 June 2019, 23:17

Quote:

Originally Posted by Mongoose

ok,
fitted the battery back in the rib yesterday.
I have a positive and negative cable going from battery to a battery isolator.
The wiring loom in a corrugated 35mm pipe also runs along by the battery box going from centre consul and back to engine.
From this loom is a black cable about 4mm in diameter that also connects directly to the battery.
I just don't know if it came off positive or negative!
I did connect it to the negative battery terminal thinking it would be less of a issue if it was wrong,and everything seems to work-gauges/engine starting/ VHF/Plotter etc, but im 80% sure it was originally on the positive!
Should I just leave alone, or should I try it on the positive?
I don't really want to start frying fuses etc!

Check your bilge pump, as that will be wired directly to the battery ....

charliee · 05 June 2019, 06:17

I’m with Gpsguru, it will be a direct feed to the bilge, as this should not be wired behind the isolation switch.

Mongoose · 05 June 2019, 06:24

Thanks, I’ll check.
The bilge is controlled from the switch panel on the console though.
That’s what made me question myself.

I should have marked it! Lol.
Can’t really trace as it disappears into the loom.
I’ll have to get the multimeter out!!!

charliee · 05 June 2019, 06:45

Yes, it’s wired to a switch but the bilge should be powered directly to the battery.

Test the console switch and the auto function, I think it should be connected to the positive side but may be wrong

boristhebold · 05 June 2019, 06:46

would recomend using a multimeter to help map out the wiring and draw a diagram with all wiring, switches, fuse bars, batts, lights and components that will help now and in the future.

Poly · 05 June 2019, 07:04

Mongoose - yes a fat black wire goes into the loom but usually it has to come out somewhere.

Bilge pumps aren’t always wired to bypass isolator switches - it depends if the person who fitted it ever intended it to be used and left afloat with the isolator off.

jambo · 05 June 2019, 08:40

I would definitely check the pump as I have both feeds as I leave on mooring so the direct feed is better for the electrics.

Mongoose · 05 June 2019, 09:03

Thanks all.
I will check with multimeter, but it does sound as if it should be on live as I originally expected, and it seems likely it,s the bilge pump feed.
Will report back.